Abstract

The voltage noise spectrum associated with velocity fluctuations is calculated for submicron n+nn+ GaAs structures in the framework of a closed hydrodynamic approach based on the velocity and energy conservation equations. Transit‐time effects are found to substantially influence the noise spectrum in a wide frequency range. The good agreement found with Monte Carlo simulations validates the proposed theoretical approach. We predict a minimum noisemeasure at the frequency of 250 GHz for the considered structure.